* It may be a good idea to use {{ic|1=systemctl --type=service}} to ensure that no other service is running that may want to configure the network. Multiple networking services will conflict.

* It may be a good idea to use {{ic|1=systemctl --type=service}} to ensure that no other service is running that may want to configure the network. Multiple networking services will conflict.

+

* Unlike netcfg, netctl fails to bring up a [http://en.wikipedia.org/wiki/Network_interface_controller NIC] when it is not connected to another powered up NIC. To solve this problem, follow instructions in the [[#Multiple_profiles|Multiple profiles]] section on this page, even if you have one single NIC on your system.

Required reading

Configuration

netctl may be used to introspect and control the state of the systemd services for the network profile manager. Example configuration files are provided for the user to assist them in configuring their network connection. These example profiles are located in /etc/netctl/examples/. The common configurations include:

ethernet-dhcp

ethernet-static

wireless-wpa

wireless-wpa-static

For wireless settings, use wifi-menu -o will generate the config file in /etc/netctl.

To use an example profile, simply copy one of them from /etc/netctl/examples/ to /etc/netctl/ and configure it to your needs:

# cp /etc/netctl/examples/wireless-wpa /etc/netctl/profile

Once you have created your profile, make an attempt to establish a connection using the newly created profile by running:

# netctl start profile

Note: 'profile' is the file name, not including the full path. Providing the full path will make netctl return with an error code.

If issuing the above command results in a failure, then use journalctl -xn and netctl status profile in order to obtain a more in depth explanation of the failure. Make the needed corrections to the failed configuration and retest.

Automatic operation

Just one profile

If you are using only one profile, once that profile is started successfully, it can be enabled using

# netctl enable profile

This will create and enable a systemd service that will start when the computer boots.

Note: The connection to a dhcp-server is only established if the interface is connected and up at boot time (or when the service starts). In order to have an automatic connection established on cable connect, proceed to #Multiple Profiles.

Multiple profiles

Whereas with netcfg there was net-auto-wireless.service and net-auto-wired.service, netctl uses netctl-auto@interface.service for wireless profiles, and netctl-ifplugd@interface.service for wired profiles. In order to make the netctl-auto@interface.service work for wireless interfaces, the package wpa_actiond is required to be installed. In order to make the netctl-ifplugd@interface.service work for wired interfaces, the package ifplugd is required to be installed. Configure /etc/ifplugd/ifplugd.conf accordingly. Automatic selection of a WPA-enabled profile by netctl-auto is not possible with option Security=wpa-config, please use Security=wpa-configsection instead.

To set preferred wired profile for auto-connecting specify AutoWired=yes in that profile. By default on failure ifplugd will pass to other DHCP wired profiles, then to static ones. If you don't want it to do so, set ForceConnect=yes.

Once your profiles are set and verified to be working, simply enable these services with

For static IP configuration make sure the Address= variables have a netmask after the IP (e.g. Address=('192.168.1.23/24' '192.168.1.87/24') in the example profile).

If you setup a wireless profile according in the wireless-wpa-configsection example, note that this overrides wpa_supplicant options defined above the brackets. For a connection to a hidden wireless network, add scan_ssid=1 to the options in the wireless-wpa-configsection; Hidden=yes does not work there.

It may be a good idea to use systemctl --type=service to ensure that no other service is running that may want to configure the network. Multiple networking services will conflict.

Unlike netcfg, netctl fails to bring up a NIC when it is not connected to another powered up NIC. To solve this problem, follow instructions in the Multiple profiles section on this page, even if you have one single NIC on your system.

Passphrase obfuscation (256-bit PSK)

Users not wishing to have the passphrase to their wireless network stored in plain text have the option of storing the corresponding 256-bit pre-shared key (PSK) instead, which is calculated from the passphrase and the SSID using standard algorithms.

Make sure to use the special non-quoted rules for Key= that are explained at the end of netctl.profile(5).

The key that you put in the profile configuration is enough to connect to a WPA-PSK network, which means this procedure is only good to hide the human-readable passphrase but will not prevent anyone with read access to this file from connecting to the network. You should ask yourself if there is any use in this at all, since using the same passphrase for anything else is a very poor security measure.